What in the World is an “Escaping Closure” in Swift?

This article provides a clear explanation of escaping closures in Swift, starting with Apple's official definition. It describes how a closure escapes a function when it is passed as an argument but called after the function returns. The author covers common scenarios that give rise to escaping closures, such as storing the closure in a mutable array as state or using it in asynchronous callbacks. The article is aimed at Swift developers who are moving from consuming APIs to designing their own, and it highlights why the Swift compiler requires explicit annotation for escaping closures. It includes code examples and practical insights for API designers.